Railway-traffic-controlling apparatus



F. H. NICHOLSON.

RAILWAY TRAFFIC CONTROLLING APPARATUS. APPLICATION IL'ILED MAY-1B. 1920.

1,35 552 Patented Oct. 26,1920.

II JVENTOR a z-M h/w ATTORNEY UITED STTES PATENT omen.

FRANK H. NICHOLSON, 0F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPDBATION OF "PENNSYLVANIA.

BAILWAY-TRAFFIC-CONTROLLING APPARATUS.

Specification of Letters Patent. Patented Oct. @6, 1920.

Application nled May 18, 1920. Serial No. 882,368.

To all whom it may concern: I

Be it known that I, F ANK H. ilicnonson, a citizen of the United States, residing at Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Railway-Trafiic-Controlling Apparatus, of which the following is a specification.

My invention relates to railway traffic controlling "apparatus, and particularly to signaling apparatus for stretches of single track over which traflic moves in both directions. The invention is particularly well adapted to systems of single track signaling wherein the track is divided into successive ing the operation of the signals in the man-' ner set forth.

I will describe one form ofga-pparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing isa diagrammatic view showing one form and arrangement of apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1 designate the track rails of a single trackway railway C over which trafiic moves in both directions. The track is divided 5 into a plurality of successive blocks of which only one block AB is shown in the drawing, the rails of this block being electrically separated from the rails of the adjoining blocks by insulated joints 2.

Located adjacent the middle of the block A--B is a transformer T, the primary of which is connected with a transmission line 4 which is constantly supplied with alternating current by suitable means, suchas a generator 5. One secondary 3 of the transformer T is connected across therails of the i of relay block AB at or near the middle of this block. Located adjacent the ends of the block are two track relays P and P each comprising two stator windings 6 and 7, a rotor 10 and two rotor-operated contacts 8 and 9. Winding 6 of each relay is connect ed across the track rails at or near the correspondinlg end of the block. Winding 7 ,is constantly supplied with alternating current from the secondary of a transformer T, the primary of which is connected with the transmission line 4. Similarly, the stator winding 7 of track relay P 'is constantly supplied with alternating current from the secondary of a transformer T, the primary of which is connected with the transmission line 4.

It will be. seen from the foregoing that the trackway apparatus for the block. A-B comprises what is known as a centerfed track circuit, that is, a track circuit having a source of current near the middle of the block and two track relays adjacent the ends of the block. As is well understood, when a train moving toward the right enters the block A-B it will open track relay P at once, but it will not open track relay P until the train reaches a point near the middle of the block. As the train recedes from the middle of the-block track relay P will again close, but track relay P will remain open until the train has left the block. The operation of the track relays during a train movement from right to left is similar and will be understood without further explanation.

The reference character N designates a three-position relay comprising a rotor 13, a stator winding 11, two additional stator windings 12 and 12", and a series of con tacts 14, 15 21 operatively connected with the rotor 13. The stator winding 11 is constantly supplied with alternating current from a secondary 32 of transformer T, and the additional stator windings 12 and 12 are at times supplied with alternating current in the manner hereinafter set forth. The control of this relay will be best understood by explaining the operation ofthe relay as a train passes through the block. When the block is unoccupied, relay N is deenergized, because the circuits for both ad ditional windings 12 and 12 are open; the

contact fingers of the relay then occupy their cuit passes from the left hand terminal of transformer T through wire 43, back point of contact 9 of track relay P wires 49 and 50, contact 30-19, wire 60, winding 12, wire 61, contact 18--28, wires 62 and 63, and common wire 0 to the right hand terminal of the secondary of transformer T When the upper wire of transmission line 4 is positive, the left hand terminal of the secondary of transformer T is positive (remembering that the current in the secondary of a transformer is displaced 180 from the current in the primary), and at such time the current may be said to pass downwardly through winding 12". Currentof this relative polarity in winding 12* cooperates with current in winding 11 in such manner as to cause the contact fingers of relay N to swing to the right. This does not cause contacts 19-30 and 18-28 to open, however, because of the length of the segments 28 and 30 forming parts of these contacts. As the train approaches the middle of the block, it causes track relay P to open, and, of course, this operation of relay P occurs before track relay P closes. The opening of relay P closes a holding circuit for relay N, which passes from the right hand terminal of the secondary of transformer T through wire 33. back point of contact 9 of track relay P wires 46. 41 and 64:, contact 26-17. wire 65. winding 12. wire 66, contact 1624, wire 67. wire 63, and common wire 0 to the left hand terminal of the secondary of transformer T When the upper wire of transmission line 4 is positive, so that the left hand terminal of the secondary of transformer T is positive, the current in this circuit may be said to pass upwardly through winding 12. That is, the current thus supplied to winding 12 is of such relative polarity as to cooperate with the current in winding 11 to hold the contacts of relay N in their extreme right hand position even after winding 12" becomes de'energized. After the train has passed the middle of the block track relay P closes, thereby opening the first circuit for relay N, but this relay continues to be energized owing to its holding circuit until the train passes out of the block.

I will now assume that a train moving toward the right passes along the track. When this train enters block A-B it opens track relay P thereby closing the following pick-up circuit for relay N-from the right hand terminal of the secondary of transformer T, through wire 33, back point of contact 9, wires 40 and 41, contact 23-46, wire 66, winding 12, wire 65, contact 1725, wires 67 and 63, and common wire 0 to the secondary of transformer T". The relative polarity of this current in winding 12 is opposite to the relative polarity of the current in this winding when the holding circuit traced above is closed. It follows, therefore, that relay N is now ener-.

gized in the opposite direction so that its contact fingers are swung to the left. When track relay P opens, a second holding circuit for relay N is closed, WlllClhClIClllt asses from the secondary of transformer through wire43, back point of contact 9, wires 49, 50 and 68, contact 27-48, winding 12, wire. 60, contact 19--29, wires 62 and 63, and common wire 0 to the secondary of transformer T The relative polarity of this current in winding 12 is opposite to that of the current supplied to this winding by the pick-up circuit traced above, and so the current now supplied to winding 12* cooperates with the current in winding 11 to maintain the contacts of relay N in their extreme left hand positions.

Located adjacent, the left hand end of block A-B is a roadside signal S which governs traflic into the block from this end. A similar signal S is located adjacent the right hand end of the block for the purpose of governing traflic into the block from this end. These two signals will hereinafter be termed the end signals. and as here shown they are in the form of semaphore, signals, each indicating stop or proceed according as the semaphore is in the horizontal or an inclined position. The block is further provided with two intermediate signals S and S located in advance of the end signals S and S respectively. As here shown, these intermediate signals are in the form of light signals. each comprising a green lamp G and a red lamp R, the signal indicating proceed when the green lamp is illuminated,'and stop when the red lamp is illuminated.

The end signal S is provided with a circuit which passes from the right hand terminal of the secondary of transformer T through" wire 33, front point of contact 9 of traclrrelay P wires 34: and 35, contact 14 of relay N, wire 36, contact 8 of relay P wire 37, operating mechanism of signal S, wiref38, and common wire 0 to the left hand terminal of the secondary of transformer T. It will be seen that in so far as this circuit is concerned, signal S will indi cate proceed'onl when both track relays are energized and the three-position relay N is deenergized. The circuit just traced is provided, however, with a branch around the front point of contact 9 of relay P and contact 14 of relay N, which branch passes through the back point of contact 9, wires 40 and 41, contact 22-15 of rela N, and

' cuit which passes from the secondary of transformer T 'through wire 43, from-point of contact 9 of track relay P wires 44 and 45, contact 21 of relay N, wire 46, contact 8 of track relay P wire 47, operating mechanism of signal S, and wire 48 and common wire 0 to the secondary of transformer T. This circuit is likewise provided with a branch around contact 21 and the front point of contact 9 of relay P which branch passes through the back point of contact 9 of relay P wires 49 and 50, contact 31-20, v

and wire 51 to wire 46. It follows that signal S will indicate proceed when relay P is closed and relay P is open, provided that relay N is energized in such direction that its contacts are swung to the left' so that contact 3120 is closed.

The circuit for the proceed lamp G of signal S is from the secondary of trans former T through wire 33, front point of contact 9 of relay P wires 34 and 52, lamp G, wires 53 and 54 and common wire 0 to the secondary of transformer T. -The oilcuit for the stop lamp R of this signal is from the secondary of transformer T through wire 33, back point or track relay P wires 40 and 55, lamp R, wire 54, and common wire 0 to the secondary of transformer T. It will be seen, therefore, that signal S is controlled only by the track relay P and that this signal will indicate proceed or stop according as this relay is closed or open.

Signal S is controlled in a similar manner by trackrelay P so that this signal indicates proceed or stop "according. as the track relay P is closed or open. The circuit for the proceed lamp 'of signal S is from the secondary of transformer T through Wire 43, front point of contact 9 of relay P wires 44 and 56, lamp G, wires 57 and 58, and common-wire 0 to the secondary of transformer T The circuit for the stop lamp R of this signal is from the secondary of transformer T through wire 43, back point of contact 9 of track relay P wires 49 and 59, lamp R, wire 58 and common wire 0 to the secondary of transformer T The operation of the entire apparatus is as follows and S indicate proceed. When a train mov ing toward the left enters block A-B, the

opening of track relay P opens the circuit for signal S at contact 8, so that thls slgnal moves to the stop position. The opening of. track relay l? also opens at contact 9 the circuit for signal S", so that this signal also moves to the stop position. The opening of contact 9 of track relay P also opens the circuit for the proceed lamp G of signal S and closes the circuit for the stop lamp R of this si al, so that signal S chan es to stop. T e opening of track relay B closes a pick-up circuit for relay N, so that this relay becomes energized in such direction that its contact fingers are swung to the right. As the train approaches the middle of the block, it opens track relay P which relay in turn closes a holding circuit through winding 12 of rela N, which circuit keeps the relay energize in such direction that its contact fingers are to the right of the vertical. The reversal of contact 9 of track relay P also causes signal S? to change to the stop indication. After the train has passed the middle of the block track relay P again becomes energized, whereupon the branch for the circuit of signal S around contact. 14 of relay'N and the front point of contact 9 of relay P becomes closed, so that si a1 S returns to the proceed osition. following train moving toward the left may then enter block AB under a proceed signal. Signal S remains at stop, however, as long as any part of the train occupies the block, and signal S indicates stop as long as the train remains in the section between signal S and the left hand end of the block. When the train passes out of the block, track relay P closes, thereby opening the holding circuit for relay N so that this relay returns to its denergized condition. Signal S and signal S then, of course, assume their proceed indications and all parts of the apparatus are again in the conditions shown in the drawing.

The operation of the apparatus during the passage of a train from left to right will be understood from the foregoing without further explanation.

Although I have herein shown and described only one form of apparatus embodylng my invention, it is understood that various changes and modifications may be made therein Within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a block of railway track over which traflic moves in both directions, two track relays for said block ar ranged to be operated. successively by a' train passing through the block, the relay first operated remaining in operated condition a three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is first operated by a train entering the block, and for keeping said three position relay energized in such direction until the train leaves the block, and signals for said. block controlled by said three position relay.

2. In combination, a block of railway track over which trafiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a

three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is first operated by a train entering the block and for keeping said three position relay energized in such direction until the train leavesithe block, two signals located respectively at the ends of the block for governing traflic into the block, a circuit foreach signal controlled by a front contact of each track relay, and a branch in the circuit for each signal around thefront contact of the track relay associated with the opposite on of theblock and including a back contact of the latter relay and a contact of the three position relay which is closed when a train enters the block at the end at which the signal is located.

3. In combination, a block of railway track over which trafli'c moves in both directions, two track relays for said block arranged to be operated successivel by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is first operated by a train entering the block, and for keeping said three position relay energized in such direction 'until the train leaves the block, two signals located respectively adjacent the two ends of the block for governing traflic into the block, a circuit for each signal controlled by a front contact of each track relay and by a contact of the three position relay which is closed onl when the relay is deenergized, and abranc in the circuit for each signal around'jthe front contact of the track relay associated with the opposite end of the block and the said contact of the three position relay, said branch including a back contact of the lastmentioned track relay and a (-ontact of the three position relay which is closed when a train enters the block at the end adjacent which the signal is located.

4. In combination, a. block of railway track over which trafiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a three position relay, means controlled by said track relays for energizing said three position relay in one d'rection or the other according as one track relay or the other is first operated by'a train entering the block, and for keeping said three position relay energized in such direction until the train leaves the block, two signals located respectively at the two ends of the block for governing traflic into the block, a circuit for each signal controlled by a contact of the three position relay which contact is closed only when the; relay is de'nergized, and a branch in the circuit for each signal around the sald contact of the three position relay and including a contact of the three position relay which is closed when a train enters the block at the end adjacent which the signal is located. 7

51 In combination, a block of railway track over which traflic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until the other relay has been operated, a three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is first operated by a train entering the block,

and for keeping said three position relay energized in such direction until the train leaves the block, two'signals located respectively at the two ends of the block for governing traflic into the block, a circuit for each signal controlled by a contact of the three position relay which is closed only when the relay is deenergized, and a branch in the circuit for each signal around the said contact of the three position relay, said branch including a back contact of the track relay associated with the opposite end of the block and a contact of the three position relay which is closed when a train enters the block at the end adjacent which the signal is located.

6. In combination, a block of railway track over which trafiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is operated by a train entering the block at either end for causing both signalsto indicate stop andfor permitting the signal in the rear of the train to indicate proceed after the train has passed an intermediate point in the block.

7 In combination, a block of railway track over which trafiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a three position relay, means controlled by said track relays for energizing said three position relay in one direction or the other according as one track relay or the other is first operated by a train-entering the block and for keeping it energized in the original direction until the train leaves the block, two signals located respectively adjacent the two ends of the block for governing traflic into the block, two interme-' diate signals located respectively in advance of said two end signals, means controlled by said relays when operated by a train entering the block for causing both end signals .,to indicate stop and for permitting the end signal in the rear of the train to indicate proceed after the train passes an intermediate point in the block, and means con-.

trolled by said relays when operated by a train passing through the block for causing the intermediate signal nearest to the exit end of the block to indicate stop until the train passes an intermediate point in the block and for ermitting the intermediate signal nearest tl ie entering end of the block to indicate proceed until after the train has passed said intermediate point in the block.

8. In combination, a block of railway track over Which traflic moves in both directions, two track relays for said block ar ranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condileaves the block, two end signals located respectively adjacent the two-ends of the block' for governing traific into the block, two intermediate signals located respectively in advance of the two end signals, means controlled by a train entering the block; for causing both end signals to indicate stop and for keeping the end-signal at the exit end of the block at stop condition until the train leaves the block but permitting the end signal at the entrance end'of the block to indicate proceed after the train has passed an intermediate point in the block, and means for causing each intermediate signal to indicate proceed or stop according as the track relay first operated by: a train entering the block at the end farthest from said signal is in the non-operated or operated condition.

9. In combination, a block of railway track over which traffic moves in both directions, two tracks relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until after the other relay has been operated, a three position relay, means convtrolled by said track relays for energizing said three position relay in one direction or the other according as onetrack relay or the other is first operated by a train enter ing the block, and for keeping said three position relay energized in such direction until the train leaves the block, two end signals located respectively adjacent the two ends of the block for governing traffic into the block, two intermediate signals located respectively in advance of the two end'signals, a circuit for each end signal controlled by a front contact of each track relay and by a contact of the three position relay which is closed only when such relay is deenergized, a branch in the circuit for each end signal around the front contact of the track relay associated with the opposite end of the block and around ,the said contact of the three position relay said branch including a back contact of the lastmentioned track relay and a contact of the three position relay which is closed only when the 110 relay is energized by a train enterin the block at the end adjacent which the signal is located, a proceed indication circuit for 1 each intermediate signal controlled by a front contact of the track relay first oper- 115 ated by a train entering the block at the end farthest from the signal, and a stop indication circuit for each intermediate signal controlled by a back contact ,of the track relay first operated by a train entering the block at the end farthest from such intermediate signal.

10. In combination, a block of railway track over which trafiic moves in both directions, two track relays for said block ar-- a winding constantly supplied with current and two additional windings each arranged to cooperate with the first-mentioned winding in such manner that the relay is energiz'ed when either additional winding is supplied with current and that the relay is energized in one direction or the other accordlng as the current supplied to the additional winding is of one relative polarity or the other, means controlled by said track relays for supplying current to one additional winding of said three position, relay when the first track relay is operated by a train entering the block and for supplying current to the other additional winding of the three position relay when the second track relay is operated by such train, the relative polarities of the two currents thus supplied to the additional windings of the three osition relay being such as to energize tile relay in the same direction, and signals for said block controlled by said three osition relay. 1

11. n combination, a block of ,railway track over which traflic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condi-- tion until after the other relay has been operated, a three position relay comprising a winding constantly supplied with current and two additional windings, means controlled by the track relay first operated by a train entering the block for supplying current to one additional winding or the other of said three position relay, according as the train is moving in one direction or the other, the relative polarities of said currents being such that the thr ee position relay is energized in one direction or the other, means controlled by the track relay last operated by a train passing through the block for supplying current to the additional winding of said three position relay which was not energized by the entrance of the train into the block, the-current thus supplied to the three position relay being such as to keep said relay energized in the direction in which it was energized by the entrance of the train into the block, and signals for said block controlled by said three position relay. i

12. In combination, a block of railway track over which trafiic, moves in both directions, a three position relay, means controlled by a train passing through said block for energizing said relay in one direction or the other according as the train enters the block at one end or the other and for keeping said relay energized in such direction until the train leaves the block, and

signals for said block controlled by said relay.

13. In combination, a block of railway track over which trailic moves in both directions, a three position relay, means controlled by a train passing through said block for energizing said relay in one direction or the other according as the train enters the block at one end or the other and for keeping the relay energized in such direction until the train leaves the block, two signals located respectively at the two ends of the block for governing traflic into the block, a circuit for each signal controlled by a contact of said relay which is closed only when the relay is denergized, and a branch in the circuit for each signal around said relay contact and including 'a contact of said relay which is closed when a train enters the block at the end at which the signal is located.

14. In combination, a block of railway track over which traflic moves in both directions, a three position relay comprising a winding constantly supplied with current .and two additional windings each arranged to cooperate with the first-mentioned winding to energize the relay, means controlled by a train passing through said block for supplying current to one additional winding when the train enters the block and for supplying current to the other additional winding after the train passes an intermediate point in the block, the relative polarities of thetwo currents thus supplied to the additional windings being such as to energize the relay in the same direction, and signals for the said block controlled by said re ay.

15. In combination, a block of railway track over which traflic moves, in. both directions, a three-position relay comprising a winding constantly supplied with current and two additional windings each arranged to cooperate with the first-mentioned winding to energize therelay, means controlled by a train entering theblock at one end or the other for supplying current to one additional winding or the other, the relative p0- larities of such currents being such as to energize the relay in one direction or the other, and means controlled by a train after the train passes an interme iate point in the block for supplying current to the additional winding which is not energized by such train entering the block, the relative polarity of the current thus supplied to the last-mentioned additional winding being such as to keep the relay energized in the direction in which it was energized due to the entrance of such train into the block.

In testimony whereof I afiix my signature in presence of two witnesses.

FRANK H. NICHOLSON.

Witnesses:

A. HERMAN Wnomnn, E. P. CRUX. 

